Download Institution of Engineering and Technology

ACTIVITY
Night light
TIME NEEDED
30–40
minutes
BADGE
Build a milk bottle beacon using simple
electronics and some household items
SUITABLE FOR CUBS, SCOUTS, EXPLORERS, NETWORK
YOU WILL NEED
l Thin card
l PP3 battery clip
l A single hole punch or craft knife
l Wire strippers
l Bare Conductive paint – either
pots with brushes or paint pens
l Ultra bright LEDs x 2
l Light dependent resistor (LDR) x 1
(resistance: light 5K, dark 20M)
l A transistor (number BC547)
l 100K resistor
l 9V battery
l A clean, dry 1 pint milk bottle with lid
1
2
Download the template for the
night light circuit board from
scouts.org.uk/IET and print on card.
Cut out the shape of your circuit.
Punch holes in the circuit where
the two LEDs and the LDR will go.
3
Strip off 1cm of the insulation
from each of the battery clip
wires then bend out the wires on the
components to make them sit flat.
Create the circuit by painting
over the lines with the Bare
Conductive paint.
Put the components in place.
The LDR must have its sensor
facing down through the hole. Push
the LEDs through their holes so the
wires lie along the Bare Conductive
Paint. The negative wire on the LED
is shorter and should be on the side of
the hole marked ‘–’.
Fix the components in place with
small blobs of paint and then
paint over the wires. Allow to dry.
Roll the card, insert it into the milk
bottle and screw the lid back on.
4
5
6
LDR
sensor
LDR
sensor
LEDs
LEDs
Transistor
100k
resistor
14
Bare
Conductive
paint
9V battery
PP3 battery clip
The Institution of Engineering and
Technology (IET) partners the Scout
Electronics Activity Badge.
PARTNER
OUTCOMES
This activity is an introduction to
electronic engineering, helping
Scouts to recognise common
components and the functions
they perform in electronic circuits.
MORE INFORMATION
Equipment for this activity
can be purchased cheaply from
suppliers such as kitronik.co.uk;
rapidonline.com or maplin.
co.uk. Visit scouts.org.uk/IET for
more information and activities.